Cookie in a cupcake?

So as a prize for doing very well on a reading test yesterday I brought a bag of mini Twix bars in for my students today. As I was munching on one I thought how fabulous a "twix cupcake" would be (for those who might not know, a Twix candy bar is a crunchy shortbread cookie covered in caramel then covered in chocolate). My question is, what kind of cookie can I bake into a cupcake that would still be crunchy like the cookie in a twix bar? I baked some chopped-up oreos into a cookies 'n cream cupcake and they turned totally soft and just baked into the batter and you didn't even know they were there. It was the Hershey's Perfect Chocolate Cake recipe which is very thin so maybe that made them soft? Anyhoo... I don't want to waste another bag of cookies of batch of cupcakes without hearing from someone else who has made a cupcake like this and still had a crunch cookie. Anyone?

I do a chocolate chip cookie dough type cupcake where you put cookie batter in the middle and it usually bakes up pretty good, definitely has some crunch, as I have always wanted it to be more like dough.